The Supreme Court on Wednesday asked the CBI to respond to a plea filed by one of the convicts in former Prime Minister Rajiv Gandhi's assassination case seeking recall of the apex court's May 1999 order upholding his conviction.

A bench comprising Justices Ranjan Gogoi and R Banumathi asked the probe agency to file its response to the application filed by convict A G Perarivalan within three weeks and posted the matter for hearing on February 21.

In its May 1999 order, the apex court had upheld the death sentence of four convicts, Perarivalan, Murugan, Santham and Nalini in the assassination case.

However, in April 2000, the Tamil Nadu governor commuted the death sentence of Nalini on the basis of state government's recommendation and an appeal by former Congress president Sonia Gandhi.

Later the top court had on February 18, 2014 commuted the death sentence of Perarivalan to life imprisonment, along with two other condemned prisoners, Santhan and Murugan, on grounds of a delay of 11 years in deciding their mercy pleas by the Centre.

During the hearing today, advocate Gopal Shankaranarayanan, representing Perarivalan told the court that he has filed an application seeking recall of the 1999 judgement by the top court and the CBI should respond to it.

In his application, Perarivalan has said that he is languishing in jail for the past 26 years.

Yesterday, the apex court had asked the Centre to take a decision within three months on a 2016 letter by Tamil Nadu government seeking its concurrence on releasing seven convicts in the assassination case.

The letter written on March 2, 2016, had said that while the state government has already decided to release the seven convicts, it is necessary to seek the Centre's concurrence as per an apex court order of 2015.

Rajiv Gandhi was assassinated on the night of May 21, 1991 at Sriperumbudur in Tamil Nadu by a woman suicide bomber, identified as Dhanu, at an election rally. Fourteen others, including Dhanu herself, were also killed.